Apparatus for mounting contact screen in a process camera

ABSTRACT

This invention provides apparatus for mounting a contact screen in a process camera such that the screen can be moved relative to a film backing in a direction perpendicular to the optical axis of the camera to and from a position where the screen is spaced from the film backing and a position where the screen is juxtaposed against the film backing without chafing of scratching the screen or film surfaces.

United States Patent Nishikawa et al.

Apr. 2, 1974 APPARATUS FOR MOUNTING CONTACT SCREEN IN A PROCESS CAMERAInventors: Yukio Nishikawa, 9-2, Kamigamo Sakuramachi; Yoshio Nagao,9-7, Kamigamo Sakuramachi, both of Kyoto; Iwao Hirose, 720-48 UrushidaNishi Imacho, Shiga, all of Japan Filed: Dec. 15, 1972 Appl. No.:315,471

US. Cl 355/18, 96/116, 355/53 Int. Cl. G03b 27/42 Field of Search355/53, 18, 74; 96/45,

References Cited UNITED STATES PATENTS 4/1925 Hay et al. 96/116 12/1936Disque et al.... 96/116 4/1938 Powers 1. 96/116 8/1951 Sussin 96/1162,981,625 4/1961 Powers et al. 96/45 3,041,931 7/1962 Anander 96/1163,063,337 11/1962 Anander 96/116 3,068,748 12/1962 Schutt et a1.....355/73 3,467,524 9/1969 Gruver 355/18 3,593,228 7/1971 Miyauchi 355/18FOREIGN PATENTS OR APPLICATIONS 1,522,038 6/1969 Germany 355/18 PrimaryExaminerRichard L. Moses Attorney, Agent, or Firm-Lilling & Siegel [57]ABSTRACT This invention provides apparatus for mounting a contact screenin a process camera such that the screen can be moved relative to a filmbacking in a direction perpendicular to the optical axis of the camerato and from a position where the screen is spaced from the film backingand a position where the screen is juxtaposed against the film backingwithout chafing of scratching the screen or film surfaces.

7 Claims, 7 Drawing Figures APPARATUS FOR MOUNTING CONTACT SCREEN IN APROCESS CAMERA This invention relates to mechanism for handling acontact screen in a process camera and applying the screen to a filmsheet on the face of a vacuum film support.

Heretofore, applying a contact screen to a vacuum film support for thepurpose of producing a half-tone negative or positive in a roll filmtype process camera, there has been generally employed either a methodin which a contact screen is lowered, by a suitable driving mechanism,from its original position suspended at a position in front and above afilm support to a position juxtaposed to the entire surface of the film,and then a roller or other suitable means is rolled or slided over thecontact screen thereby placing the contact screen in intimate contactwith the film, or a method in which two rollers are used for the doublepurposes of fitting and detaching of the contact screen as for instancedisclosed in U.S. Pat. No. 3,068,748.

However, the former method has a drawback that when the contact screenis moved up and down, static electricity is generated between thecontact screen and the film or film support to attract the former to thelatter, and as a consequence, friction takes place between the contactscreen and the film support to produce scratches on the contact screen,resulting in deteriorating the product of photographic film andexcessively shortening the life of the contact screen. The latter methodof U.S. Pat. No. 3,068,748 has the advantage of not permitting an easyaccess to replace the screen or film because of the facing relationshipof the screen and film holder and resulting in a relatively thicker,less streamlined device.

The present invention provides a novel methodand mechanism for handlinga contact screen in a process camera, which method and mechanism arefree of the conventional defects such as referred to above and whichalso permit attachment and detachment of the contact screen relative tothe film with no fear of causing damage to the screen or film.

In accordance with the present invention, there is provided in aphoto-mechanical camera, a support frame for a flexible contact typehalf-tone screen with the frame being displaced in a directionperpendicular to the optical axis of the camera from a film backing; thesupport frame and film backing are relatively movable to and from aposition where they are in a spaced relation and in a position wherethey are juxtaposed to each other. A contact type half-tone screen issupported in the support frame such that one end is rigidly connected tothe frame and the second edge is resiliently attached to the frame. Thescreen is to be pressed against a film sheet on the face of the filmbacking when the screen support frame and the film backing are movedfrom their spaced relation into juxtaposed relation. A film sheet canpreferably be attached to the film backing by vacuum. When the screensupport assembly and film backing are moved into juxtaposedrelationship, the screen support assembly and the film backing initiallyare in contact along only one of each of their edges; the opposite edgesare maintained apart by a movable spacer means. The screen is pressedinto contact with a film on the film backing by a roller which initiallypresses against the screen adjacent the edge in contact with the filmbacking and which moves along the face of the screen so as to graduallypress the screen into contact with afilm on the film backing along theentire surface of the screen. That is, a combination of the resilientattachment at one end of the screen and the movable function of thespacer means permits the entire screen to be gradually pressed intocontact against the film along its entire surface. The roller means ispreferably moved along guide means which insures that the roller movesalong a plane parallel to the surface of the screen; preferably theroller is biased so as to press perpendicularly against the surface ofthe screen. The roller can be automatically operated, as with anelectric motor, or it can be manually operated. The roller, however, isnot activated until the film backing and the screen retainer assemblyare in the juxtaposed relationship. As the roller means returns to itsoriginal position, the screen is gradually pulled perpendicularly awayfrom the film backing until the screen is completely out of contact withthe film and the screen retainer assembly and the film backing can bedisplaced from their juxtaposed relationship.

The invention is now described in detail by way of a preferredembodiment with reference to the accompanying drawings, in which:

FIGS. 1 to 4 are diagramatic sketches depicting the movement of theapparatus of this invention in practicing the method of the presentinvention;

' FIG. 5 is a front view showing the apparatus of the invention;

FIG. 6 is a vertical sectional side view taken along the line 66 of FIG.5; and

FIG. 7 is an enlarged vertical sectional view taken along the line 77 ofFIG. 5.

In the preferred embodiment illustrated in the drawings, the screenretainer assembly is vertically movable from a position above the filmbacking downwardly to a position juxtaposed to the film backing. Inother words, along a direction perpendicular to the optical axis of thecamera. This relative vertical movement can of course be obtained bymounting the screen retainer assembly or the film backing so that eitheror both can be vertically moved within the process camera. In thepreferred embodiment shown in the drawing, the screen retainer assemblyis vertically movable.

Referring to the drawings, the apparatus according to the presentinvention includes a screen retainer assembly 10 which is connected tocord 11. The cord 11 can move the assembly 10in a vertical direction toa position adjacent to a vacuum suction type film backing 12 having anupper edge 112 and a lower edge 113, which carries a film 13 on itsfront side, this is the position as shown in FIG. 1. The screen retainerassembly 10 comprises a holder 14 and a screen retaining frame 15, withthe lower end of the holder pivotally joined to the upper end of thescreen retaining frame by a horizontal pin 16. The holder 14 has an armportion 17 that projects horizontally from its top end and which carriesat its end an engaging roller 18 pivoted about a horizontal axis 18a.

Provided inside the upper edge of said retaining frame 15 is a screenholding or clamping means 19 which is rigidly attached to the frame 15but which can be moved up and down to carry screens of different sizesby operating screws 20 and which is adapted to clamp the top edge of ascreen 21; the bottom edge of said screen being clampedby' a clampingmeans 22 whichis joined to the lower edge 116 of said retaining frame 15by means of tension springs 23, whereby said screen 21 is positioned ina tense stretched state within said retaining frame 15.

A lever 24, projecting outwardly from the film backing 12, is pivotablyconnected about a horizontal pin 25 to a lower part of said film backing12. This lever 24 is given a rotational restorative force by a spring26. The top surface of the projecting portion of lever 24 shouldpreferably, as shown, project transversly downwardly in front of thefilm backing 12, so that when the retaining frame 15 descends to itslower limit as described later, the projecting portion of said lever 24pushes the bottom edge 116 of said retaining frame 15 forwardly to keepit from touching the film surface.

Provided vertically below the roller 18, is a stopper 27, immovable withregard to the film backing, adapted to engage with said roller 18 whenthe retaining frame 15 has descended to its lower limit. The distancesbetween the roller 18 and stopper 27 and between the bottom edge 116 ofsaid retaining frame 15 and the projecting edge of said lever 24 are sogiven that said stopper 27 will engage the roller 18 after the rear sideof the bottom portion of said retaining frame 15 touches the projectingend of said lever 24.

Vertical guide rails 31 are rigidly attached to either side of the filmbacking 12. The upper portions 32 of guide rails 31 are inclinedoutwardly away from the film backing 12. Runners 30 are movablyconnected to the guide rails 31 by three rollers 33, 34 and 35 each. Asshown in FIG. 7, the runners 30 include bearings, generally indicated by'29; the bearings each comprise I the bearing body 36, a bearing box 38and a spring 37,

loaded in the bearing box 38, such that the bearing body 36 is biasedalong a direction perpendicular to and towards the guide rails 31. Aroller 28 is rotatably connected to the bearings 29 at each end.

The roller is normally positioned at the upper end of the guide rails 31above and in front of the film backing 12. When the screen retainerassembly is moved into juxtaposed position relative to the film backing12, the roller 28 is moved into position so as to lightly press thescreen 21 against the front face of the film backing 12. The pressure isexerted by the springs 37 in each runner 30 and retaining springs 23. Asthe roller is further lowered, it continues to press the screen 21against the film backing 12 as shown in FIGS. 1 to 4, until, as in FIG.4, the entire surface of the screen 21 is pressed against the filmbacking 12.

In operating the apparatus described above a screen 21 is placed in thescreen retainer assembly 10 and film 13 is placed on the film backing12. The screen retainer assembly 10 is then lowered, the bottom portionof the retaining frame contacts the projecting end of the lever 24 onthe film backing 12; the retainer assembly 10 continues to be lowereduntil the roller 18 engages stop means 27, the bottom portion of theretaining frame 15 is then pushed forwardly by the projecting end oflever 24 so that the screen retainer assembly 10 is pivoted aboutconnecting pin 16 such that the inside face of the upper part of screen21 contacts the upper part of the front side of the film 13 in the filmbacking 12.

The roller 28 is then activated, and lowered in a transverse directiontowards the screen 21 until the roller 28 presses lightly against theupper portion of the screen 21; the roller is then lowered in averticaldirection defined by the guides 31, continuing to press the screen 21against the film 13 until the entire screen 21 is in contact with thefilm 13. The roller is biased against the screen by the springs 37 inthe runner body 30 and by the springs 23 which resiliently attach thescreen 21 to the screen retainer assembly 10.

The above operation can be carried out manually, i.e., the screenretainer assembly 10 lowered manually and the roller means 18 activatedmanually, or automatically by, for example, electric motors which wouldcause the movement of the screen retainer assembly 10 and the filmbacking 12 relative to each other and in a direction perpendicular tothe optical axis of the camera followed by automatic activation of theroller means 21 when the screen retainer assembly 10- and film backing12 are in the desired juxtaposed position.

When the contact between the screen and the film is completed, thefoller 28 can be returned to its original position; the screen 21, asthe roller 28 returns to its original position, springs away from thefilm 13 in a direction substantially perpendicular to the surface of thefilm 13 so as to avoid any chafing between the two surfaces. When theroller is in its uppermost position, the screen retainer assembly 10 ispulled in a vertical direction by the cord 11, pivoting the top edge ofthe screen retainer assembly 10 out of contact from the film backing 12and the screen retainer assembly 10 can then be moved away from the filmbacking 12.

According to the present invention, as described above, a contact screen21, which is to be attached to a film 13, is first lowered to a positionin front of the film 13 in such a manner that the former will not touchthe latter, and then the screen is stuck fast to the film surface bypressing the former against the latter with a roller 28 from a directionsubstantially perpendicular to said film surface. For detaching thescreen, said roller 28 is raised up whereby the portion of the screenwhich said roller 28 has passed is stripped off successively by dint ofsaid springs 23 which pull the bottom edge of said screen. Thus, thereis no possibility that the film and screen chafe against each other whenattaching ordetaching the screen to or from the film and hence thescreen remains free of any damage of abrasion and is thereforeappreciably elongated in its service life.

What is claimed:

1. An apparatus for mounting a contact screen in a process cameracomprising: i

l. a film backing having a first edge and a second edge;

2. a screen retainer assembly comprising a screen retainer frame, afirst screen anchoring element rigidly attached to one edge of thescreen retainer frame, land a second screen anchoring elementresiliently attached to a second edge of the screen retainer frame, saidfilm backing and screen retainer assembly being relatively movable in adirection perpendicular to the optical axis of the camera to and from aposition where the film backing is spaced from the screen retainerassembly and a position wherein the film backing and the screen retainerassembly are juxtaposed in contact along one of each of their edges;

3. movable spacer means for separating the film backing from the screenretainer assembly at the other of each of their edges;

4. roller guide means; and

5. a roller, movably attached to the roller guide means, designed andadapted to press a screen in the screen retainer assembly against thefilm backing initially at the edge in contact with the film backing andto move along the face of the screen so as to move the screen graduallyinto contact with the film backing along its entire surface, when thescreen retainer assembly and film backing are moved into the juxtaposedposition.

2. The apparatus of claim 1 comprising moving means for moving thescreen retainer assembly in a vertical direction and wherein the screenretainer assembly is operatively connected to the moving means.

3. The apparatus of claim 2 comprising in addition stop means immovablewith respect to the film backing and wherein the screen retainerassembly comprises in addition holder means pivotally connected to thetop edge of the screen retaining frame and stop-engaging means rigidlyattached to the holder means, the stop means and engaging means being sodisposed that upon their mutual engagement the top edge of the screenretaining frame is pivoted into contact with the top edge of the filmbacking.

4. In a process camera comprising a film backing for supporting a filmand a screen retainer assembly for holding a contact type half-tonescreen in position against a film on the film backing, an improvementwhich results in close adhesion of the screen to the film surface duringthe processing but permits ready separation of the film withoutscratching or chafing of the film and screen against each other, theimprovement comprising movable spacer means resiliently attached to thefilm backing at one edge, projecting outwardly from the film backing; ascreen retainer frame within the screen retainer assembly comprising afirst screen anchoring element rigidly attached to one edge of thescreen retaining frame; a second screen anchoring element resilientlyattached to a second edge of the screen retaining frame; means formoving the screen retainer assembly in a direction perpendicular to theoptical axis of the camera to and from a position where the film backingis spaced from the assembly and a position wherein the film backing isin juxtaposition with the screen retainer assembly, the movable spacermeans being so placed that the screen retainer assembly and film backingare in contact only along one of each of their edges; roller guide meansrigidly attached to the film backing and in movable relationshipthereto; a roller assembly movably supported by the guide means and soarranged'that when the screen retainer assembly is in juxtaposedrelationship to the film backing, the roller is 'guided to press theface of a screen in the screen retainer frame against the film backingand can be moved parallel to the film backing so as to press the entirescreen against the film backing in a direction substantiallyperpendicular to the film backing.

5. The process camera of claim 4, wherein the screen retainer assemblymoves in a vertical direction relative to the film backing.

6. The process camera of claim 5, wherein the screen retainer assemblymoves from a position above the film backing downwardly to a position injuxtaposed relationship to the film backing, the elements of theassembly being arranged and adapted to accomplish this result.

7. The apparatus for mounting a contact screen in a process cameracomprising a film backing; a screen retainer assembly comprising ascreen retaining frame, a first screen anchoring element rigidlyattached to the top edge of the screen retaining frame, a second screenanchoring element resiliently attached to the lower edge of the screenretaining screen; means for moving the screen retainer assembly to andfrom a position above and horizontally forward of the film backing faceand a position in juxtaposition with the film backing face; holder meanspivotally connected to the screen retainer assembly; a stop-engagingportion projecting rearwardly from the holder means towards the filmbacking rigidly connected to the holder means; stop means in immovablerelationship to the film backing; movable spacer means resilientlyattached to the film backing and projecting forwardly from the filmbacking towards the screen retainer assembly; the combined apparatusbeing designed and adapted such that when the screen retainer assemblyis lowered into its juxtaposed position with the film backing, the stopmeans being places so as to engage the stop-engaging means after thelower edge of the screen retainer assembly engages the movable spacermeans such that the upper edge of the screen retainer assembly ispivoted inwardly to contact the upper edge of the film backing and thelower edge of the screen retainer assembly is pivoted forwardly awayfrom the lower edge of the film backing; roller guide means attached tothe film backing; a roller assembly designed and adapted to move alongthe roller guide means when the screen retainer assembly is in itsjuxtaposed position with the film backing so as to pressingly engage thescreen and press the screen against the film backing and to movedownwardly along the screen so as to gradually press the entire face ofthe screen against the film backing, the roller means being positionedalong a substantially horizontal axis.

1. An apparatus for mounting a contact screen in a process cameracomprising:
 1. a film backing having a first edge and a second edge; 2.a screen retainer assembly comprising a screen retainer frame, a firstscreen anchoring element rigidly attached to one edge of the screenretainer frame, /and a second screen anchoring element resilientlyattached to a second edge of the screen retainer frame, said filmbacking and screen retainer assembly being relatively movable in adirection perpendicular to the optical axis of the camera to and from aposition where the film backing is spaced from the screen retainerassembly and a position wherein the film backing and the screen retainerassembly are juxtaposed in contact along one of each of their edges; 3.movable spacer means for separating the film backing from the screenretainer assembly at the other of each of their edges;
 4. roller guidemeans; and
 5. a roller, movably attached to the roller guide means,designed and adapted to press a screen in the screen retainer assemblyagainst the film backing initially at the edge in contact with the filmbacking and to move along the face of the screen so as to move thescreen gradually into contact with the film backing along its entiresurface, when the screen retainer assembly and film backing are movedinto the juxtaposed position.
 2. a screen retainer assembly comprising ascreen retainer frame, a first screen anchoring element rigidly attachedto one edge of the screen retainer frame, /and a second screen anchoringelement resiliently attached to a second edge of the screen retainerframe, said film backing and screen retainer assembly being relativelymovable in a direction perpendicular to the optical axis of the camerato and from a position where the film backing is spaced from the screenretainer assembly and a position wherein the film backing and the screenretainer assembly are juxtaposed in contact along one of each of theiredges;
 2. The apparatus of claim 1 comprising moving means for movingthe screen retainer assembly in a vertical direction and wherein thescreen retainer assembly is operatively connected to the moving means.3. movable spacer means for separating the film backing from the screenretainer assembly at the other of each of their edges;
 3. The apparatusof claim 2 comprising in addition stop means immovable with respect tothe film backing and wherein the screen retainer assembly comprises inaddition holder means pivotally connected to the top edge of the screenretaining frame and stop-engaging means rigidly attached to the holdermeans, the stop means and engaging means being so disposed that upontheir mutual engageMent the top edge of the screen retaining frame ispivoted into contact with the top edge of the film backing.
 4. In aprocess camera comprising a film backing for supporting a film and ascreen retainer assembly for holding a contact type half-tone screen inposition against a film on the film backing, an improvement whichresults in close adhesion of the screen to the film surface during theprocessing but permits ready separation of the film without scratchingor chafing of the film and screen against each other, the improvementcomprising movable spacer means resiliently attached to the film backingat one edge, projecting outwardly from the film backing; a screenretainer frame within the screen retainer assembly comprising a firstscreen anchoring element rigidly attached to one edge of the screenretaining frame; a second screen anchoring element resiliently attachedto a second edge of the screen retaining frame; means for moving thescreen retainer assembly in a direction perpendicular to the opticalaxis of the camera to and from a position where the film backing isspaced from the assembly and a position wherein the film backing is injuxtaposition with the screen retainer assembly, the movable spacermeans being so placed that the screen retainer assembly and film backingare in contact only along one of each of their edges; roller guide meansrigidly attached to the film backing and in movable relationshipthereto; a roller assembly movably supported by the guide means and soarranged that when the screen retainer assembly is in juxtaposedrelationship to the film backing, the roller is guided to press the faceof a screen in the screen retainer frame against the film backing andcan be moved parallel to the film backing so as to press the entirescreen against the film backing in a direction substantiallyperpendicular to the film backing.
 4. roller guide means; and
 5. Theprocess camera of claim 4, wherein the screen retainer assembly moves ina vertical direction relative to the film backing.
 5. a roller, movablyattached to the roller guide means, designed and adapted to press ascreen in the screen retainer assembly against the film backinginitially at the edge in contact with the film backing and to move alongthe face of the screen so as to move the screen gradually into contactwith the film backing along its entire surface, when the screen retainerassembly and film backing are moved into the juxtaposed position.
 6. Theprocess camera of claim 5, wherein the screen retainer assembly movesfrom a position above the film backing downwardly to a position injuxtaposed relationship to the film backing, the elements of theassembly being arranged and adapted to accomplish this result.
 7. Theapparatus for mounting a contact screen in a process camera comprising afilm backing; a screen retainer assembly comprising a screen retainingframe, a first screen anchoring element rigidly attached to the top edgeof the screen retaining frame, a second screen anchoring elementresiliently attached to the lower edge of the screen retaining screen;means for moving the screen retainer assembly to and from a positionabove and horizontally forward of the film backing face and a positionin juxtaposition with the film backing face; holder means pivotallyconnected to the screen retainer assembly; a stop-engaging portionprojecting rearwardly from the holder means towards the film backingrigidly connected to the holder means; stop means in immovablerelationship to the film backing; movable spacer means resilientlyattached to the film backing and projecting forwardly from the filmbacking towards the screen retainer assembly; the combined apparatusbeing designed and adapted such that when the screen retainer assemblyis lowered into its juxtaposed position with the film backing, the stopmeans being places so as to engage the stop-engaging means after thelower edge of the screen retainer assembly engages the movable spacermeans such that the upper edge of the screen retainer assembly ispivoted inwardly to contact the upper edge of the film backing and thelower edge of the screen retainer assembly is pivoted forwardly awayfrom the lower edge of the film backing; roller guide means attached tothe film backing; a roller assembly designed and adapted to move alongthe roller guide means when the screen retainer assembly is in itsjuxtaposed position with the film backing so as to pressingly engage thescreen and press the screen against the film backing and to movedownwardly along the screen so as to gradually press the entire face ofthe screen against the film backing, the roller means being positionedalong a substantially horizontal axis.